pyclean: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/pyclean - from package: python-minimal

You may install the required package with command apt-get install {package}

Error in other languages:
pyclean: bevel nie gevind nie
pyclean: comandă negăsită
pyclean: comando não encontrado
pyclean: commande introuvable
pyclean: command not found
pyclean: käsku ei ole
pyclean: không tìm thấy lệnh
pyclean: komanda nerasta
pyclean: Kommando nicht gefunden.
pyclean: kommandot finns inte
pyclean: komut yok
pyclean: nie znaleziono polecenia
pyclean: níor aimsíodh an t-ordú
pyclean: no se encontró la orden
pyclean: no s'ha trobat l'ordre
pyclean: opdracht niet gevonden
pyclean: parancs nem található
pyclean: perintah tidak ditemukan
pyclean: príkaz nenájdený
pyclean: příkaz nenalezen
pyclean: команда не найдена
pyclean: командата не е открита
pyclean: 命令找不到
pyclean: コマンドが見つかりません